Are the streamed videos on iplayer (and other online TV sites) supposed to be squashed (black bars top and bottom) when viewed in full screen mode ?

On my widescreen TV its squashing them when they shouldn't be leaving black bars at the top and bottom of the screen.  I have tried reinstalling flash but that didnt help.
Surely they are not supposed to be like that ?

The videos on YouTube play fine in full screen though.

RESOLVED:  I was running my desktop at 1024x768.  When I set it to full resolution of TV 1920x1080 the videos went full screen.